In 46 breast-fed children affected with otitis or otoantrite, it was investigated on the role of seric immunoglobulines which necessarie are in e transitory lacking period. In the 50% of the tested cases in has been checked a lack of IgG particularly remarkable, beyond the limits of range of the values specific in the breastfed child. As e conclusion, the lack in gammaglobulines is a factor which favours the rising of infection.